Overview of Network Selection and Vertical Handover Approaches and Simulation Tools in Heterogeneous Wireless Networks

Wireless communications constitute a vital sector within telecommunications. Multiple wireless technologies, such as 4G, 5G, WiFi, etc., are available to users. One of the most important benefits of wireless communications is enabling the user mobility. However, this feature often requires handover between access points or base stations. Moreover, modern user equipment has the support for multiple wireless technologies, which brings possibility for network selection and vertical handover (VHO) between different wireless technologies. The importance of network selection and VHO has been further amplified in recent years because satellite communications are increasingly perceived as extensions to terrestrial wireless technologies. This paper provides a comprehensive review of the current state-of-the-art methods, algorithms and techniques used in network selection and VHO. It delves into the underlying mathematical approaches and models that underpin each method. Detailed performance comparison with listed advantages and disadvantages of the analyzed methods is also presented in the paper.